Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to an equipment for
blood sample collection of the type described in the
introductory clause of claim 1, i.e. an equipment com-
prising a hypodermic needle and a needle holder, which
also includes a receiver cylinder for an evacuated vial.
This vial has a perforatable end cap which at the inser-
tion of the vial into the holder is perforated by an
interior needle therein, such that hereby a suction
connection is established between the specimen vial and
the outer sampling needle. In so doing the collection of
blood will be supported by the vacuum in the specimen
vial, such that advantageously essentially thinner
sampling needles than in the conventional, so-called
open systems may be used.
When using such a closed system it is customary
that in connection with the said holder a needle is used
having a holding piece which can be connected to a stub
on the holder and which has a two-sided protruding
needle which is pointed at both ends and constitutes
both the sampling needle and the associated inner needle
in the holder for cooperation with the specimen vial.
However, various problems are connected with this simple
design, among others that the twin needles concerned are
dangerous to handle. They are also problematic in those
cases where it is relevant to fill more vials from one
and the same insertion of the sampling needle, as in the
intermediary periods blood may freely seep from the
needle. This, however, is sought counteracted by using a
resilient lining tube on the inner needle, this tube in
its free state covering an outer, radial outlet opening
in the needle, while the tube is axially pressed to-
gether for exposure of this opening by insertion of the
needle through the end cap of the specimen vial, but the
corresponding closing of the opening at the withdrawal
of the vial is not fully effective.
According to the USA Patent specifications Nos.
20~9~fi
4,166,450 and 4,312,362 sampling devices have been con-
trived where a separation is introduced between the
outer, fixed or loose sampling needle and the inwardly
projecting needle for connection to the vial, in that an
intermediate chamber is provided with transparent walls,
which are claimed to provide a visual indication that
the sampling needle upon insertion has hit a blood vein
such that connecting the vial may wait until it has been
ascertained that the sampling will succeed. This may
well cut back on certain abortive sampling attempts and
a futile use of a number of vials, but in practice this
problem is not abundant.
It is more significant that at the same time the
environmental problem regarding use of double projecting
needles is solved, viz. by the inner needle of the
holder constituting a separate portion which both be-
fore and after use is situated connected to and pro-
tected by the surrounding holder, which does not appear
to be recognized previously as a particular advantage on
its own.
Comparing the said patent specifications it has
been found natural that in the said discontinuous con-
nection between the inner and outer needle, special
valve portions may be used instead of the said resilient
covering tube over the inner needle. One of the specifi-
cations (4,312,362) discloses that a valve slide is
brought to uncovering a hole at the side of the inner
end of the interior needle in response to the vacuum
which is applied by the connection of the vial, but this
construction will hereby be limited to a one-off use for
filling of a single vial only, as no means are present
for resetting the valve slide.
In the other of the said USA Patent specifications,
viz. No. 4,166,450, an application of an inner needle is
proposed, which is limited displaceable in a tight guide
in such a manner that at the insertion of the vial into
202~2~
the holder, it is caused to be moved forward to perfo-
rating a thin separator diaphragm adjacent an ante-
chamber, which is connected to the rear end of the sam-
pling needle, prior to the opposite end of same needle
by the insertion of the vial penetrating the thicker end
cap of the vial. This necessitates that the thus dis-
placeable needle portion is connected to radially out-
wardly projecting guiding and end stop portions entail-
ing problems with regard to a free movability in sur-
rounding, non-ventilated guiding chambers.
The purpose of the invention is to provide a blood
specimen collection system of the said kind by which the
necessary valve function can be ensured in a suitable,
effective and constructively simple manner.
According to the invention this is achieved by the
blood specimen device being embodied as indicated in the
characterizing clause of claim 1. The valve element is
hereby constituted by the inner needle itself, which at
the insertion of the vial is pushed to an open position
in that the closed front of the needle is brought into
engagement with the bottom end of the cylinder, such
that the needle thereupon at its pointed tailend is able
to perforate the seal of the vial by further insertion
of the latter. At retraction of the vial the needle will
be brought along to the closed position without any dis-
placement problems, whereby the equipment can be reused
for insertion of a new vial. For the simplicity of the
construction it is of significance that the inner needle
and the outer sampling needle or its holding base are
placed radially offset from one another, as the inner
needle can thereby be opened by being pressed against a
stop, which lies offset from the connecting passage to
or from the sampling needle; hereby it can be totally
avoided that the inner needle must be connected to spe-
cial, problem incurring guiding and stop portions, cf.
USA Patent specification No. 4,166,450.
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It is hereby an extremely lucky or significant
circumstance that also for other reasons it is advanta-
geous that the inner and the outer needle are radially
offset from one another, viz. by a central positioning
of the inner needle and an eccentric or peripheral plac-
ing of the outer needle. By the central placing of the
inner needle this will cooperate with a central perfora-
tion area on the inserted vials, whereby it may suffice
for these to have a comparatively narrow perforation
area, and by the eccentric positioning of the outer
needle it is possible to insert the needle into the
patient at a shallow angle relative the actual body
surface, which is advantageous for a good insertion
safety and a resulting light fixing of the holder to the
part of the body. This advantage in itself is clearly
disclosed in the said USA Patent specification No.
4,166,450 where the advantage is achieved only at the
cost of considerable problems with regard to the guiding
and valve function of the inner needle which is lying
co-axially to the outer needle.
If required the holder may be made of a transparent
material such that the insertion of the vial may wait
until it is ascertained that a trace of effusing blood
from the sampling needle appears at the bottom portion
of the holder.
The invention, which also comprises a particularly
advantageous design of the vials, is explained in
further detail in the following with reference to the
drawing, in which:-
Fig. 1 is an exploded perspective view of a set ofcollection appliances constituting part of a collection
system according to the invention,
Fig. 2 is a lateral sectional view of two of the
appliance components,
Fig. 3 is a more detailed sectional view of an end
portion of the applied holder,
- 2029~?~
Figs. 4 and 5 are sectional views of an embodiment
of a vial for use in the system, and
Fig. 6 is a sectional view of another embodiment of
the vial.
In Fig. 1 is shown a collection set comprising a
sampling needle 2, a holder 4 and a vial 6. The needle 2
is made in the usual manner for injection needles, viz.
comprising a holder portion 8 having a one-sided pro-
jecting needle 10 and a bushing 12 at the other side of
a collar 14. The bushing 12 is intended for insertion
into or screwing onto a connector stub 16 on the holder
14, this being easily performed when a cover 18 is
placed over the needle, such cover encasing the needle
10 and being removed after the fitting, when the appli-
ance is required.
The holder 4 is tubular having a closed end at the
stub 16 and an opposing open end where the tube com-
prises a protruding collar 20. Inside the holder 4 and
in connection with the stub 16 a central needle 22 is
placed projecting slightly inwardly into the holder,
however nowhere near to the area at the open end, such
that in practice this needle is inaccessible to contact.
The vial 6 is an evacuated glass, the mouth of
which is covered by a cap 24 that can be perforated by
the needle 22 when the vial is inserted into the holder
4. The perforation requires a certain pressure, but the
vial can be pressed in with quite a heavy force, using
the collar 20 as a grip just like when pressing home a
syringe piston.
The appliances can be applied thus that the needle
10 upon assembly with the holder 4 is inserted into a
vein whereupon the vial 6 is inserted and is pressed
into the holder 4. When the needle 22 penetrates the cap
24, the vacuum in the vial 6 spreads to the foremost
needle 10 and the blood is drawn to the vial 6. When
this is filled as required it can simply be removed from
2~2~Q~6
the holder, which is easily done because the vial in the
inserted position protrudes substantially rearwardly
from the holder. If no more samples are to be collected,
the needle 10 may be withdrawn and provided with the
cover 18, after which the unit 2l 4 may be taken to
waste collection.
If yet another or some more samples are to be col-
lected, the needle 10 may remain in the vein, and upon
removal of the vial 6 a new vial 6 may be inserted into
the holder. As mentioned previously it is hereby desir-
able that use is made of a valve-blocking of the needle
22. In principle this can be brought about in the same
way as with the hitherto used rearward protruding needle
portions on the needles 2, viz. by covering of the
needle 22 with a resilient, narrow case which at the
pressing against the cap 24 will become perforated and
be pushed forward to exposing the needle, but according
to the invention it is preferred to make use of a valve
device, which is effective at the fixed end of the
needle.
~ his is rendered possible by virtue of the needle
22 being subjected to a forwardly displacing force by
the insertion of the vial 6 already before the cap is
perforated, just as the needle, by the frictional en-
gagement with the perforation portion of the cap, will
be affected by an outward-directed force, when the vial
is removed, and hereby it is possible to lodge the
needle thus axially displacable that at the insertion
and removal of the vial it will be displaced between two
positions in such a manner that the needle in itself
hereby can act as a relevant valve member.
Such an arrangement is shown in further detail in
Fig. 2 and particularly in Fig. 3. The needle 22 is
mounted in a passage in a holder plug 26, which is
pressed in to a position right against the closed end of
the holder 4, and outermost this passage communicates
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with a recess 28 in the plug 26, the needle from the
beginning being mounted such that with its rearmost
collar portion 30 it abuts on the recess bottom at the
relevant end of the said passage for the needle. Close
to its outer circumference the recess 30 is in open
connection with a central passage 32 through the stub 16
on the holder 4, this stub being placed eccentric on the
end portion of the holder, while the needle 22 is situ-
ated centrally in the holder. The end of the needle at
the collar 30 is closed tightly, preferably by being
pressed together and folded out as shown by 31.
The eccentric position of the stub 16 is tantamount
to the outer needle 10 being situated close to the ex-
tension of an outer wall area of the holder 4, which is
an advantage at the insertion of the needle into the
vein, as the holder then permits a very acute-angled
insertion of the needle into the vein.
The portion of the inner needle 22 which is accom-
modated in the passage in the plug 22 is provided with
side openings 34 which are kept closed by the passage in
the position shown by solid lines in Fig. 3. However, at
the insertion of the vial 6 the needle will be pushed
back when the cap 24 is pressed against its point, and
hereby the needle will be displaced to the position
shown in dashed lines in which the collar 30 pushes
against the front of the holder 4, and in which the side
openings 34 communicate with the recess 28 and thereby
with the passage 32 through the stub 16, i.e. the needle
22 will thereby communicate with the outer needle 10.
Immediately thereafter the point of the needle 22 will
penetrate the cap 24 as the needle 22 is now prevented
from further displacement, and the vacuum in the vial
will thus spread to the collection needle 10.
When the vial 6 is extracted, the needle 22 will be
carried along the first stretch as care is taken that
its frictional connection with the cap 24 is stronger
2 ~
than its friction with the passage through the plug 26,
and the first result of the extraction will thus be that
the needle 22 is brought back to the position in which
the side openings 34 are situated inside the said pas-
sage, i.e. closed outwardly, and as also the free tail
end of the needle is closed at 31, the interior of the
needle is thus completely blocked from the connection
with the recess 28 and the needle 10. The remaining
vacuum in the vial 6 will, however, affect the interior
of the needle 22 all the time until the cap is moved
outwardly past the needle point and there will be an
insignificant risk that hereby even a mere trace of a
drop of blood will be deposited on the central outside
of the cap. At the insertion of a new vial 6 the
described course will merely be repeated.
It is essential that the relations are thus adapted
that the friction of the needle 22 against the per-
forated cap 24 is larger than its friction with the
passage in the plug 26, and therefore it is also signi-
ficant that the cover of the vial is adapted according
to this condition. The vials used so far for the purpose
are provided with a cap consisting of a simple rubber
plug with a central depression facilitating the penetra-
tion by the needle, but with the prior art it was need-
less to pay the said special regard to friction, and
these plugs were therefore not provided with any espe-
cially well calibrated perforation portion. By the in-
vention it is preferred to work with a newly innovated
type of vial, where the perforatable element is a disc
of rubber or a corresponding material which is clamped
by means of a screw cap mounted on a threaded element
closely connected with the vial glass, as such an embo-
diment with increased safety can be adapted to the pur-
pose and besides shows further advantages.
~ n example of such a vial is shown in Figs. 4-5
where a plug 40 is inserted in the vial mouth so as to
2~2~026
seal against the vial by means of a sealing ring 42, the
plug having a protruding portion 43 which is provided
with an outer threading. The plug has a completely open
central passage 44, and on top of the plug a rubber disc
45 is laid, which is tightened against the plug by means
of a screw cap 46 in the overside of which is provided a
central hole 48. The unit 40, 45, 46 can be assembled in
advance for closing the vial at the evacuation thereof,
and at the use the needle 22 needs only penetrate the
disc 45. It is not crucial whether this perforation
takes place exactly centrally, but structurally it is
convenient letting the needle 22 be centrally placed.
As shown in Fig. 4 the sealing ring 42 is provided
as a flat disc having a hole 49, the diameter of which
is noticeably smaller than the outer diameter of the
plug
area 50, on which the ring be mounted by insertion from
the free end of the plug portion 40. By this insertion
the disc 42 will be deformed as shown in Fig. 5, viz. to
forming of an upwardly conical expanding tube portion,
which by insertion into the vial can tighten firmly
against the inside of the latter even though tolerance
deviations occur with respect to the inner diameter of
the vial and the outer diameter of the sealing disc 42.
At the manufacture of the evacuated vials 6 the
assembled plug body can be inserted into the vial while
this is kept under vacuum.
When a vial has been filled to a required degree,
it is normally desirable immediately upon extraction
from the holder 4 to 'deflate' the vial to remove the
remaining vacuum therein. This may simply be done by
unscrewing the screw cap a little and then screwing it
home again; at its edge the sealing disc 45 is secured
to the screw cap such that it is compulsorily lifted by
the unscrewing.
The blood sample can be taken out after unscrewing
02~02~
the cap 46 either by pouring out or by drawing by a pi-
pette. The plug unit shown has the great advantage that
it is thus easily opened without removing the plug, and
that the plug, however, is removable from a smooth
cylindrical vial which thereby after centrifuging can
cooperate with a serum separator. It has previously been
attempted to provide the vial glass itself with an outer
thread for a screw cap, but this is hardly possible
without deformation of the smooth cylindrical inside,
and thereby the vial is made unsuitable for cooperation
with a usual serum separator.
In Fig. 6 is shown another embodiment of the vial,
where the holding plug for the non-illustrated screw cap
comprises a bushing portion 52, which can be placed on
the outside of the vial mouthing and tighten against the
latter by means of an embedded sealing ring 54. This
embodiment, which likewise cooperates with a smooth-
walled vial, is advantageous by being easily 'deflated'
when this is required, as one may press against the
lower edge of the portion 52 and thereby produce a cap-
sizing.
